// Copyright (C) Kumo inc. and its affiliates.
// Author: Jeff.li lijippy@163.com
// All rights reserved.
// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU Affero General Public License as published
// by the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU Affero General Public License for more details.
//
// You should have received a copy of the GNU Affero General Public License
// along with this program.  If not, see <https://www.gnu.org/licenses/>.
//
#pragma once

#include <pollux/common/strings/string_impl.h>

namespace kumo::pollux::functions {
    /// split_part(string, delimiter, index) -> varchar
    ///
    ///     Splits string on delimiter and returns the part at index.
    ///     Field indexes start with 1. If the index is larger than the
    ///     number of fields, then null is returned.
    template<typename T>
    struct SplitPart {
        POLLUX_DEFINE_FUNCTION_TYPES(T);

        // Results refer to strings in the first argument.
        static constexpr int32_t reuse_strings_from_arg = 0;

        // ASCII input always produces ASCII result.
        static constexpr bool is_default_ascii_behavior = true;

        MELON_ALWAYS_INLINE bool call(
            out_type<Varchar> &result,
            const arg_type<Varchar> &input,
            const arg_type<Varchar> &delimiter,
            const int64_t &index) {
            return stringImpl::splitPart<false>(result, input, delimiter, index);
        }

        MELON_ALWAYS_INLINE bool callAscii(
            out_type<Varchar> &result,
            const arg_type<Varchar> &input,
            const arg_type<Varchar> &delimiter,
            const int64_t &index) {
            return stringImpl::splitPart<true>(result, input, delimiter, index);
        }
    };
} // namespace kumo::pollux::functions
